Temperature sensor implemented with a magnetoresistive random access memory (mram)

An integrated circuit, comprising:

• a magnetoresistive random access memory (MRAM);
• a non-volatile memory (NVM) configured to store an indication of a target bit error rate and a set of margin read reference and temperature correlations for the target bit error rate;
• and
• built-in self-test (BIST) circuitry configured to perform temperature sensing by:
• iteratively adjusting and using a margin read reference to obtain margin read data from the MRAM until a bit error rate of the MRAM achieves the target bit error rate, wherein each adjusted margin read reference is at a different offset from a normal read reference, and
• outputting a sensed temperature of the integrated circuit by using a resulting value of the iteratively adjusted margin read reference which resulted in the MRAM achieving the target bit error rate to calculate the sensed temperature.

In an integrated circuit having a magnetoresistive random access memory (MRAM), a method to sense a temperature of the MRAM, comprising:

• selecting a current margin read reference;
• performing a sweep through a sequence of addresses using the current margin read reference wherein, at each address, a normal read from the address is performed to obtain normal read data from the MRAM using a normal read reference value and a margin read from the address is performed to obtain margin read data from the MRAM using a margin read reference value determined from the current margin read reference, wherein the margin read reference value is offset from the normal read reference value;
• determining a bit error count for the sweep based on comparisons between the normal read data and the margin read data obtained at each address of the sequence of addresses;
• selectively modifying the current margin read reference based on whether or not the bit error count achieves the target bit error rate;
• and
• calculating the sensed temperature using the selectively modified current margin read reference and the set of margin read reference and temperature correlations for the target bit error rate.